


[Obligatory Beach Episode]

by Nanenna



Category: Undertale (Video Game)
Genre: Alternate Universe - Merpeople, Angst, Found Family, Gen, Humor, Mentions of Violence, Non-Verbal Frisk (Undertale), Post-Undertale Pacifist Route, Post-Undertale Pacifist Route - "I want to stay with you.", gratuitous headcanons, just a little though, mentions of eating humans
Language: English
Status: Completed
Published: 2018-11-14
Updated: 2018-11-25
Packaged: 2019-08-23 11:39:32
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 8,781
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16618277
Author URL: https://archiveofourown.org/users/Nanenna/pseuds/Nanenna
Summary: It's only been a little while since the barrier was broken and Monsterkind was freed, but somehow Frisk's friends still haven't gone to the beach yet despite it being right there! Frisk decides to fix this. Shenanigans ensue.





	1. Beach Shenanigans

**Author's Note:**

> So Frisk at one point narrates "a hundred resets" and I would like to just warn you now: that is purely an exaggeration. It may have take this Frisk quite a few resets (and at least one True Reset, which they regret) to get the happy ending everyone deserves, but it didn't take them a hundred.

Frisk looked at Sans strangely, their usually laid back friend was sitting bolt upright, his legs jittering in place like he had more energy than he knew what to do with. Everyone in the car was a bit jittery with excitement, of course, they had only been on the surface for such a short while and still hadn’t had time to go visit the beach even though the city was right next to it. Everyone was happy to make the trip once Frisk suggested it, but no one seemed half as excited as Sans if his bouncing knee was anything to go by. Frisk decided to ask him what was going on. They poked his arm.

“huh? oh, hey bucko, ‘sup?”

Frisk looked down at where Sans’s leg was still bouncing, then back up at him with a raised brow.

“i seem nervous? heh, just a bit nervous about seeing the ocean. can you blame me? the surface is huge and so different from the underground.” he turned to look out the window, the next sentence murmured so quietly Frisk almost didn’t hear it, “and it’s been so long…”

“I d-don’t blame him,” Alphys said from Frisk’s other side. “I’m a b-bit n-nervous myself.”

“Don’t be, it’s gonna be a blast!” Undyne yelled gleefully as she leaned over the back of Frisk’s seat.

“Seat belt,” Toriel called in a sing-song voice from the driver’s seat.

“DON’T WORRY, THE GREAT PAPYRUS IS ENSURING EVERYONE IS PROPERLY WEARING ALL APPROPRIATE SAFETY GEAR. ONE MUST ALWAYS TAKE SAFETY VERY SERIOUSLY.” Papyrus leaned forward in his own seat, “I MUST ADMIT, THESE SEAT BELTS HAVE QUITE THE RANGE.”

 “Well… if everyone is still strapped in,” Toriel said in a wavering voice. She seemed to be glaring at them through the rear view mirror.

“AND SINCE WE ARE ADMITTING THINGS, PERHAPS IT WILL COMFORT MY LAZY BROTHER AND NERVOUS FRIEND IF I ADMIT TO BEING JUST A TINY BIT NERVOUS AS WELL.”

 “Well I’m EXCITED!” Undyne yelled happily.

“OH, I’M EXCITED AS WELL! MORE EXCITED THAN NERVOUS EVEN, I CAN’T WAIT TO TRY THIS SEA BATHING THAT IS ALL THE RAGE. BUT! IT IS STILL! SOMETHING NEW! AND NEW THINGS CAN MAKE EVEN THE GREATEST A BIT NERVOUS.”

 Undyne nodded sagely.

 “hate to sink your hopes, bro, but i gotta remind you that bones don’t float.”

“WHAT? BUT I’VE BEEN INFORMED THAT THE SALT CONTENT OF OCEAN WATER MAKES IT DENSER THAN THE WATER WE HAD UNDERGROUND!”

 “not dense enough, bro. sorry, you’ll have to stick to the shallows. though what’s shallow for you and what’s shallow for me are gonna be two different things.” Sans leaned back with his hands behind his head and winked at Frisk, though his still bouncing knee wasn’t fooling them one bit.

 “Yeah, you’re so short!” Undyne crowed happily. “But it’s not like you’ll even try, you’ll probably lay down on the beach and go right to sleep. I can’t WAIT to get in the ocean, Surface water has been so amazing so far!”

Sans looked at Undyne out of the corner of his eye and gave a soft huff, like he didn’t believe her.

“DON’T FRET, BROTHER. WE CAN STILL ENJOY THE OCEAN EVEN IF WE CANNOT PLUMB ITS DEPTHS. OH! WE CAN BUILD SANDCASTLES! I HEAR THEY’RE A LOT LIKE BUILDING SNOWMEN.”

 “we could try building sandmen.”

“THAT SOUNDS LIKE AN INTERESTING CHALLENGE.”

 “We’re here!” Toriel said cheerfully as the van came to a stop. Everyone eagerly unbuckled and grabbed their bags as they all tried to get out at once. Frisk and Sans wisely chose to let the more energetic of their friends out first before climbing out themselves.

 Frisk hopped out and stretched, it felt nice after the drive even if it really wasn’t all that long. They made sure to be looking at Sans as he stepped out of the van and looked at the ocean for the first time. He froze, the little lights in his eye holes shrank to the tiniest pinpricks before blowing up huge. He started trembling hard enough for Frisk to hear his bones rattling before he gave out this strangled kind of wheeze, then took off running.

Frisk was startled, they had never seen Sans run before ever. Not in a hundred resets, not once since getting to the Surface. Apparently neither had anyone else because everyone simply stared after him in confusion.

Papyrus was the first to recover, “SANS?”

 Sans was already out of the parking lot, having **vaulted** over the low stone wall between the cars and the beach (rather than go through the wide gap meant for people to go through), and was running over the sand. Frisk couldn’t see his hoodie anywhere, and they were also pretty sure he’d lost both his sandals. Without missing a step he pulled his shirt off and dropped it behind him, then faltered as he tried to pull his shorts off without stopping.

 “SANS!” Papyrus dropped the things he’d been holding, there was a loud crack so something likely broke, before running full tilt after his brother.

 Like it was some sort of cue Undyne ran after him, Alphys hurrying behind at a much slower rate. Frisk started to chase as well, but Toriel scooped them up.

“My child, where are you going?”

Frisk frantically pointed at the others, looking back just in time to see Sans hit the water, then dive right into an oncoming wave. He didn’t come back up. Frisk looked back up at Toriel with wide, frantic eyes.

“Frisk, my dear, there is not much either of us can do to help…” Toriel looked down at Frisk in concern.

“EVEN IF YOU CAN’T HELP DRAG THE GOOF FROM THE WATER, YOUR HEALING TALENTS MAY BE NEEDED.”

“Oh!” Toriel and Frisk both looked to their side, where Mettaton had snuck up on them. “Mettaton, when did you arrive?”

“JUST NOW.” Mettaton motioned to where his sparkling, brand new luxury car was parked next to Toriel’s rental van. “DON’T WORRY, DARLINGS, I’LL GUARD YOUR THINGS. YOU TWO GO MAKE SURE YOUR SILLY FRIEND IS ALRIGHT.”

 “Thank you,” Toriel said before striding quickly towards the beach.

As Frisk watched, Undyne was choking and coughing as she dragged a struggling Papyrus back out of the water. By the time they arrived at the small group Undyne had graduated to just making grossed out faces while holding Papyrus back, Alphys desperately clung to him from the other side.

“UNDYNE! LET ME GO! SANS NEEDS HELP!”

Undyne coughed and made another face.

“I-i-it’s too late,” Alphys said with a squeak.

A human wearing a bright red swim suit and carrying a red… thing walked up to them. A lifeguard, Frisk realized. “Is everyone okay?”

“I do not believe so,” Toriel said as she approached. “Our friend ran into the ocean and has not come back up yet, correct?” She turned to the others for confirmation. Undyne and Alphys both nodded while Papyrus simply kept struggling. Toriel set Frisk down and gently moved Alphys aside so she could lay a gentle, restraining hand on Papyrus’s shoulder.

“Can… your friend not swim?” The lifeguard asked nervously.

“H-he’s made of b-bone,” Alphys said with a gesture towards Papyrus. “He said that bone is uh… that bone doesn’t float.”

“Oh dear,” the lifeguard said faintly. Then she looked away, down, up, then put a hand to the back of her neck and rubbed it nervously. “Okay, so I don’t know much about monsters but can he uh… breathe? Underwater??? Or uh… do skeletons even need to breathe?”

Everyone looked to Papyrus, who started to shake his head, then stopped and tilted it to the side thoughtfully. “WE BOTH NEED TO BREATHE, AND I DEFINITELY CAN’T BREATHE UNDERWATER, BUT… I’M NOT SO SURE ABOUT SANS.”

“I am confused, would he not have the same breathing limitations as you?”

“THERE WERE A FEW TIMES I CAUGHT HIM FALLEN ASLEEP IN THE BATHTUB, OR THERE WAS THE TIME WE WERE WALKING THROUGH WATERFALL AND HE SLIPPED OFF A BRIDGE. THE WATER WAS TOO DEEP AND HE HAD TO CLIMB OUT ON THE SHORE, HE COULD HAVE BEEN HOLDING HIS BREATH BUT…” Papyrus trailed off, unsure. “BUT NO MATTER HOW YOU LOOK AT IT, THE WAY HE WAS ACTING TODAY WAS JUST WEIRD!”

“Well I’ll keep an eye out for him, in the meantime please be careful and play in the ocean, responsibly, okay? And have fun!” The lifeguard gave a nervous smile and a little wave before returning to her post.

“Hey, before you go, what’s wrong with your ocean?” Undyne asked to the lifeguard’s retreating back.

“What do you mean?”

“It tastes awful! And I can’t breathe it???”

“Oh, that’s normal. Well, the bad taste is normal for humans, and we can’t breathe any water so I’m not so sure about that. Honestly, all the monsters I’ve met so far love the ocean! There was this big tentacle monster that came by the first week after you guys… uh… the first week. Friendly guy, told me how much room he finally had.”

“Ugh, whatever, thanks anyway.”

“Alright, uh… good luck.” The lifeguard waved again, then left for real this time.

“How are you feeling, Papyrus?” Toriel asked gently.

“CONFUSED, CONCERNED, AND A LITTLE ITCHY.”

Frisk figured that last one was from the sand, or possibly the salt water slowly drying on him.

“That is all very understandable. For now let us trust Sans, very likely he is fine and will return shortly. In the mean time why do we not try to enjoy ourselves a little?”

Papyrus’s shoulders slumped, “ALRIGHT.” The whole group trudged back to the van to gather up all their beach things, then go set them up in a nice little spot on the sand. While the others were blowing up floaties and laying out towels, Toriel was rubbing sunscreen all over Frisk, followed by a life vest. Frisk pouted at that.

“I know you do not like this device, but I was assured this would be enough to keep you safe. I was also informed that the ocean is very dangerous for inexperienced humans, I suppose it is very dangerous for inexperienced monsters as well. And we are all very inexperienced, so forgive me if I am a little overzealous this first time here.”

Frisk nodded, they understood that everything was very new to their family. They grabbed their kickboard and ran for the ocean, they wanted to surf! And maybe they hoped they would spot Sans out there. Eventually the others came out to join them, though they all mostly stayed in the shallows. Undyne didn’t want to try breathing ocean water again, and Papyrus and Alphys didn’t know how to swim. Frisk, of course, went over to play with them.

The day went on. Papyrus kept looking out to sea with a worried crease to his forehead, Undyne kept complaining about the water, Alphys got tired after a swimming lesson and went to join Toriel and Mettaton on the towels under their big beach umbrella. Frisk decided to go back out and ride the waves a little more.

“pssst, hey kid.”

 Frisk stopped and looked to their side. Sans was not that far away, though only his head from the nose hole up were above water. Frisk was so happy to see him again they completely forgot their kickboard to swim over to him.

“well it’s good to see you too. and hey, you’re not too bad at that, this thing seems like a bit of a nuisance though.” Skeletal hands came up to support Frisk, though something about them felt weird.

Frisk didn’t care, they were too happy to see Sans again and threw their arms over his head.

“oh, a hug too, today must be my birthday.”

Frisk gently bapped him on the head, then pointed at Papyrus and Undyne.

Sans sighed, “yeah, i know. sorry, didn’t mean to just run off like that. i can’t get too close to shore right now though, go tell them i’m back, kay?” Sans angled Frisk towards their friends and gave them a gentle nudge.

Frisk turned and pouted at Sans, why couldn’t he just go back on his own?”

“oh uh… guess you lost your swimming foam board thing.”

Frisk shook their head, the vest would be enough and the board was probably already on the beach. They decided the easiest and fastest way to take care of this was just to go get the others. They started swimming, letting the vest support them as the waves pushed them back to shore.

“Hey there ya little sea squirt!” Undyne greeted enthusiastically. “Having fun in the waves?”

“GREETINGS AGAIN, FRISK! YOU ARE QUITE ADEPT AT SWIMMING.”

Frisk swam over and grabbed onto Undyne with one hand, then held the other up.

“You want up? What? You tired already?” Undyne laughed as she picked Frisk up. Frisk just pointed out towards Sans. “What? Is something… Sans?”

“SANS!” Papyrus took off running, which was very awkward in water that was already lapping at his hip joint. He got out to where the waves were up to his chest when he had to finally give in. “SANS! CAN YOU COME CLOSER? I CAN’T GO ANY FATHER!”

Sans’s head went underwater.

“SANS!!!”

His head came back up much closer to them, the gentle motion of the waves pushing him a little closer in spurts. Undyne had followed Papyrus out as far as she could while still holding Frisk, just barely close enough for them to hear the next part.

“heeeeeeeeeey bro.”

“SANS! COME HERE RIGHT NOW!”

Sans slowly moved closer. “so uh… sorry about running off like that. i kinda lost my head there for a bit.”

“LOST YOUR… SANS! YOU JUMPED INTO THE **OCEAN** AND **DISAPPEARED**! NOW COME ALL THE WAY OVER HERE.”

“i can explain, but i don’t know if the beach is the best place for it.” Sans moved closer. Close enough for Papyrus to grab and lift him up, because that’s just what he did. Papyrus was holding Sans under his arms, lifting him as high as he could. Now that most of his upper body was out of the water Frisk could see a pair of fins on the side of his head, they looked a lot like Undyne’s but the spines were cyan and the delicate flesh stretched between them was bright yellow. And see through. There was a faint cyan glow between his ribs as well, and what looked like more cyan flesh underneath those. When the waves went low Frisk swore they saw more yellow fins.

“SANS… WHAT?”

“Why do you have FINS?!”

Sans held his hands up in a shrug, behind him something blue and yellow came very close to breaking the water’s surface. “toldya i could explain.”

“WELL YOU CAN EXPLAIN IT TO EVERYONE AT ONCE, IT’S THE LEAST YOU CAN DO AFTER THAT SCARE YOU GAVE US ALL.”

“eh, fair enough. it’s just i lost my shorts somewhere and uh… well… listen. just get me a towel or something and i’ll come out of the water.”

“NONSENSE, NO ONE CARES ABOUT YOUR ILIAC CRESTS.” Papyrus turned and started walking out of the water.

 “no bro, wait, that’s not… eh whatever. it’ll give us more privacy i suppose.”

“What do you mean by that?” Undyne asked suspiciously.

“you’ll see,” Sans said as Papyrus marched past them. He threw a wink their way as well.

As the water got shallower, Papyrus shifted Sans to under one of his arms so he’d be easier to carry. Undyne and Frisk trailed a bit behind them, mostly so they could stare at the tail floating behind them. There was a fin along Sans’s back, cyan and yellow again, instead of legs he had a long, cyan, kinda see through tail, and on the end was a large, bright yellow tail fin. Once Papyrus was out of the water and walking over the sand to the others, the tail started dragging through the sand. Sans must have not liked that because he shifted so the tail wrapped around Papyrus.

There was a loud, shrill tweet. A whistle, likely a lifeguard.

“Everyone out of the water! Siren!”

Yup, there was the lifeguard. Frisk wondered what took her so long to notice Sans. There were a few screams and quite a few humans scrambling to gather up their things and get off the beach. The lifeguard came running up to them.

“Sir! Sir I need you to put the siren down!” The lifeguard grabbed the arm that wasn’t holding Sans (thought it was holding up his tail instead) and started tugging. “Sir! Let go sir!”

“WHAT IN THE WORLD? WHAT ARE YOU DOING? I’M NOT LETTING GO, WE FINALLY GOT SANS BACK.”

“Sir for your own safety! please let go and move away from the siren!”

“WHAT ARE YOU TALKING ABOUT? SIREN? I DON’T HEAR ANY SIRENS. SANS, HAVE YOU BROKEN SOME LAW?”

“technically i’m not supposed to be on the beach, not sure if it’s a law though.”

“WHAT? ARE SKELETONS NOT ALLOWED ON THE BEACH?”

“That’s stupid!” Undyne barked angrily.

“Sir! Let go!” The lifeguard tugged harder.

“Is there a problem?” Toriel asked as she walked over to the group, Alphys and Mettaton not far behind her.

Frisk squirmed, Undyne politely let them down, they ran over to the lifeguard and gently pushed her away from Papyrus. Once Frisk was sure she was looking at them, they mimed pulling something out of their ears.

“I’m not taking out my earplugs! That’s a siren!” The lifeguard said loudly while pointing at Sans. “Sir! Please let it go! For your own safety! And the safety of everyone on the beach!”

“I don’t understand,” Undyne said in confusion. “Aren’t sirens the loud things on police cars?”

Frisk made the “remove earplugs” motion again.

“WELL WHATEVER IS GOING ON, I’M SURE IT’S ALL SOME MISUNDERSTANDING. THIS IS MY BROTHER.”

“Sir! Please! Let! Go!” More lifeguards were running towards them, the rest of the beach seemed to have emptied out by now.

“toldya it’d be easier with a towel.”

“SANS! NOW IS NOT THE TIME! NOW! IF THIS FINE… HUMAN CAN’T OR WON’T LISTEN TO US PERHAPS WE SHOULD JUST LEAVE.”

“That may be for the best,” Toriel agreed. Everyone turned and started walking towards their things, Papyrus dragging along the lifeguard that refused to let go or stop asking him to let Sans go.

The other two lifeguards made it over and practically tackled Papyrus.

“HEY!”

The next thing Frisk knew they were being handed from Toriel to Alphys (when had they even been picked up?) while Undyne and Mettaton carefully pulled the lifeguards off Papyrus and Sans. Toriel joined the fray and it was quickly over, with Toriel and Undyne standing between Papyrus (and everyone else) and the lifeguards while Mettaton hovered protectively over Papyrus.

Undyne made the “remove earplugs” motion, to which all three lifeguards shook their heads and pointed at Sans again.

“That is a siren! You’re in danger!”

“That is my dear friend Sans, who has been nothing but kind to me and my child.”

“Yeah, and he’s way too lazy to ever hurt anyone even if he did want to. I don’t see why they think he’s dangerous just because he suddenly sprouted a weird fish tail.”

“it’s ‘cause i am a siren and uh… we are kinda dangerous. to humans.”

Everyone froze and slowly turned their heads to look at Sans.

“what? it’s not like i’ve ever personally hurt a human.”

“W-wait, I’ve heard of sirens” Alphys exclaimed. “They’re uh… a human myth, right? Half human, half fish, their songs lure sailors to their deaths and they um… they devour them.”

“i’m not half human!”

“YES, HE’S CLEARLY HALF SKELETON!”

“and i wouldn’t EAT a human! but yeah, the rest of it’s right.”

“OMG!” Alphys squealed and nearly dropped Frisk in her excitement. “I mean, I’ve seen them in a few anime but I didn’t think they were real!”

“there’s lots of monsters in the ocean still, not like humans could lock us under a mountain.”

“Wait, wait, wait, you were alive for the war?” Undyne asked incredulously.”

“nah, not that old. but i was born in the ocean.”

“Okay, I took the damn earplugs out, can one of you tell me why there is a siren on my beach?!”

“THERE MUST BE SOME MISTAKE, THIS IS MY BROTHER! THE MONSTER WHO WENT MISSING EARLIER.”

“no mistake, i’m really a siren, bro. and this is getting pretty uncomfortable, mind setting me down?”

“OH, OF COURSE!” Papyrus carefully set Sans down.

The lifeguard was pinching the bridge of her nose. “So your missing friend is actually a siren, who you pulled up onto my beach full of human victims?”

“i’m not gonna sing, geez.” Sans rolled his eyes.

“You promise?” The lifeguard asked skeptically.

“i promise that i will not sing on your beach today.”

“That was strangely specific,” Undyne said.

“Alright, alright, but I want you gone.”

“yeah, yeah, whatever.”

The lifeguard turned and left, the other two trailing behind as they pulled out their earplugs.

“That was rather rude,” Toriel noted.

“YES, BUT AT LEAST THAT’S TAKEN CARE OF.” Papyrus picked Sans back up, this time carrying him princess style. They all walked over to their beach towels, where Sans was set down in the shade. He rolled onto his side and got comfortable, Frisk finally got a look at his hands, which had more bright yellow webbing between the fingers, and the yellow fins on his front. “ALRIGHT SANS, START EXPLAINING.” Everyone else settled down around Sans, Frisk absently noted that the once overcrowded beach now had a wide empty spot around them.

“okay, first things first we’re going all the way back to the war. not ALL of monsterkind got sealed in the mountain, obviously everyone still in the ocean was just fine. don’t know about anyone else though.”

“Cowards,” Undyne said angrily.

“eh, i wasn’t there, i’m not gonna judge them.”

Frisk snorted and hid their laughter behind their hands.

“anyway, i was born in the ocean, obviously. when i was a little guppy, around frisk’s age i guess, me and a bunch of other kids all swam upriver on a dare. ugh, fresh water, it’s so gross.”

Undyne snorted, “Like the ocean isn’t.”

“not to us, you freshie.”

“What’s THAT supposed to mean?!”

“just that you’re a freshwater monster, you’re not gonna like saltwater and i’m not gonna like freshwater. no big deal.”

“NO WONDER YOU HATE TAKING SHOWERS OR BATHING.”

“Why do we not just let Sans tell his story?”

“thank you, toriel. anyway, it turned into a kind of endurance contest: who would turn back first? who could go the farthest? i won, and the prize was falling into the garbage dump.” Everyone winced at that. “yeah, you think the ocean is gross? the dump is downright disgusting. anyway, i got outta there asap, put on my legs…”

“I WAS WONDERING ABOUT THAT.”

“oh yeah, the tail’s our natural form, but we can transform at well. or normally we can, i’ve been wandering around on legs for so long that it’s kinda messing with me right now, i have to wait to dry out.” Sans wriggled his tail as if to prove his point.

“That’s so f-fascinating!” Alphys said eagerly. “Do you mind letting me do some magic scans on you some time? Oh! And I have to hear you sing!”

“sure, sure, later. i did promise afterall. anyway, back to the story. got on legs and wandered around trying to figure out where i was and how to get home. that’s when papyrus’s dad found me and decided to take me in. and well… the rest you can figure out on your own.”

“And you do not wish to return to your home in the ocean?” Toriel asked.

“well sure, for a visit. i was just a kid when i fell in the underground, i grew up here. you guys are my family now. though i wouldn’t argue with picking up some salt on the way back so i can take proper saltwater baths regularly.”

“I THINK THAT CAN BE ARRANGED.”

“and hey, when we do get a house of our own up here why not something close to the ocean? something a bit secluded if we can, i gotta introduce you to the rest of my family.”

“OH! I THINK THAT’S A SPLENDID IDEA!” Papyrus grinned, Frisk supposed he must have already decided Sans’s birth family was also his family. Frisk could understand that, only Toriel may have adopted them but everyone here was family too.

**Notes for the Chapter:**

> Stuff that I couldn't cram into this: MTT shimmying into a full body suit (latex?) to keep the sand out of his joints. The fact that Sans started singing the moment he was underwater and his family is actually on their way to the beach. What other sirens look like. The giant salt water aquarium the skelebros buy for Sans to sleep in. Actually, it might be fun to some day do a follow up, both of the main cast meeting Sans's birth family and also what their home is like (I'm personally partial to a Disney's Little Mermaid style fantasy castle).
> 
>  **Bonus:**  
>  Sans: *the last note slowly fades*  
> Papyrus: WOW  
> Alphys: Oh. My. GOD.  
> Undyne: You sounded like a cat with its tail caught under a rocking chair.  
> Sans: hey, not my fault monsters can't hear the enchantment.


	2. Electric Boogaloo

**Notes for the Chapter:**

> The sequel no one asked for! Okay, that's not true, a lot of people asked for it. XD
> 
> Before we get into things a quick note: Sans strips naked shamelessly a few times in this (he can't really be a mermaid with shorts on). This goes with the HC I have that monsters don't have a sense of modesty the way Western human culture does. There are several monsters running around without pants or in just shoes or nothing at all in the game. Sans stripping to go swimming isn't meant to be in any way scandalous or sexy.

It was a few days after their trip to the beach. The group had stopped by a store and Papyrus bought the largest container of salt available, but they had both forgotten how tiny their tub was. That wasn’t going to work, not even in the short term. Sans just shrugged, they were still moving everyone up to the Surface and didn’t have a permanent home yet so a permanent solution wasn’t really possible anyway. He was fine continuing on as he had been. Papyrus had other ideas.

“THERE ARE SO MANY OPTIONS ON THE SURFACE, SANS! I’M SURE WE’LL FIND SOMETHING APPROPRIATELY TEMPORARY THAT DOESN’T HAVE YOU SLEEPING IN A TINY TUB OR OUT IN THE DRY.”

So here they were, at the local Walton Family Supermart (TM) looking through the outdoor pools, most of them were perfectly round and far too small.

“PERHAPS WE NEED AND ADULTIE POOL RATHER THAN A KIDDIE POOL?”

“oh bro, come check this one out! it’s perfect!”

Papyrus maneuvered the cart over and leaned close to the box Sans was pointing at, he squinted as he read the colorful print. “‘PARADISE LAGOON INFLATABLE KIDDIE SWIMMING POOL.’ SANS, ARE THESE THE MEASUREMENTS?”

“yeah, in feet. so uh… let’s see… i’m about the same height as frisk and they said they’re around five feet tall and this thing’s eight feet long, that’s half again so that should be plenty, even with the tail.”

“OH, LOOK AT THIS ONE! IT’S A FULL TEN FEET LONG, MORE THAN ENOUGH FOR YOUR TAIL. AND IT DOESN’T HAVE THAT TACKY, EYE SEARING, REPEATING BEACH SCENE PAINTED ON THE SIDE.”

“awwww… but i like the eye searing beach scene.”

Papyrus huffed and rolled his eye sockets, but he picked up Sans’s choice and dropped it in their cart next to the three large canisters of table salt.

“thanks, papyrus, you’re the best.”

“AND I KNOW IT, NYEH HEH HEH. SHOULD WE GET AN AIR PUMP TOO? IT IS INFLATABLE.”

Sans shrugged, “sure. we might have to re-set it up in the new house until we get a more permanent set up.” They grabbed an air pump, then Papyrus aimed their cart for the check out. “whoa, we still gotta go to the pet section. unless you want to change the water every day we’re gonna need something to keep the water circulating.”

“YOU ARE VERY NEEDY, SANS.”

“we can just put it all back and not worry about it…”

“NO! YOU HAVEN’T BEEN TAKING PROPER CARE OF YOURSELF FOR DECADES, AND NOW THAT I KNOW I’M NOT GOING TO LET THIS CONTINUE.” Papyrus turned the cart around and power walked right back to the pet section. They were browsing through the pumps, puzzling over which ones did what, when an employee found them.

“Can I help you find anything?”

“YES, WE NEED SOMETHING TO CIRCULATE A LOT OF WATER.”

“it’s gotta be saltwater,” Sans added on.

“I can certainly help with that, about how many gallons are we talking?”

Papyrus picked up the kiddie pool and flipped the box around until he found the information he was looking for. “OH, HERE IT IS, ABOUT 151 GALLONS.”

“probably a little less, it won’t need to be all the way full.”

“Keeping live fish in a kiddie pool isn’t the best for them…” The employee started nervously.

“IT’S NOT FOR A FISH, IT’S FOR MY BROTHER.” Papyrus gestured at Sans.

“to sleep in,” Sans added helpfully. “i’m a mermaid.”

“A MERMAID?”

“alphys says it’s less alarming than the s-word.”

“A mermaid,” the employee asked with raised brow. “You uh… you’re made of bones???”

Sans sighed, “papyrus, you got a picture of undyne handy?”

“CERTAINLY, BUT I DON’T SEE WHAT THAT HAS TO DO WITH ANYTHING.” Papyrus pulled his phone (a brand new one Alphys had given him after she saw his old one) out and pulled up his gallery, inside was a selfie he had taken with Undyne at the beach as they were packing everything up. He held the phone out so Sans and the employee could both see it. “THIS IS MY COOL FRIEND UNDYNE, SHE USED TO BE HEAD OF THE ROYAL GUARD! BUT SADLY THE ROYAL GUARD WAS DISBANDED WHEN ASGORE STEPPED DOWN FROM BEING KING.”

“Oh, I see. And this set up is for her?”

“NO, IT’S-”

“yeah, sure. but just as a bed, she’s amphibious and all that. and as a temporary thing, we’re all still moving up here after all.”

“Right, of course. So we have a few options, honestly you’d be better off going to a specialty pet store for something like this, but since it’s only temporary this pump is probably your best bet. It might be better to get two if you’re worried about circulation, wouldn’t want your friend suffocating in the middle of the night. If uh… if that’s a thing monsters even have to worry about??? Oh! And you might also want a tarp or something to throw over it during the day to keep dus- er… dirt and stuff from falling in while she’s not sleeping in it.”

“THAT IS AN EXCELLENT SUGGESTION. ACTUALLY, THINKING ABOUT IT WE MIGHT NEED TWO TARPS, THAT’S GOING TO BE A LOT OF WATER SPILLING EVERYWHERE WHEN YOU FIRST GET UP IN THE MORNING.”

“good idea.” Sans grabbed the offered pump and put it in the cart. “thanks for the help. c’mon bro, let’s go hit up whatever section has tarps.”

“Probably the outdoors section, especially over by the camping goods.”

“THANK YOU VERY MUCH.”

* * *

It had taken some time and a bit of research, but Sans found the perfect stretch of beach. It was a very rocky area that boardered some cliffs, just offshore was a steep drop off into the deeper ocean. Between the uncomfortable rocks and the dangerously deep water few humans tended to visit, even fewer the closer it got to night. Sans glanced nervously at the late afternoon sun reflecting off the choppy water as he stripped, each piece of clothing handed over to a widely grinning Papyrus rather than dropped to the ocean spray soaked rocks at their feet.

“so i don’t know how long this’ll take…”

“I KNOW, WE’VE ALREADY BEEN OVER THIS.”

“you remember those olde monster classes you took?”

“OF COURSE! AND TORIEL HAS BEEN HELPING ME BRUSH UP.”

“yeah, but it’s not the same, i’m pretty sure sea monsters had a different dialect even back during the war…”

“SANS! YOU’RE JUST PROCRASTINATING AT THIS POINT. NOW GET IN THE WATER AND START SINGING!” Papyrus pointed insistently at the ocean with his other hand on his hip.

“alright, thanks bro.” Sans gave him a hug before turning and walking towards the water. He’d barely taken the first step into the ocean when his tail transformed and he fell face first into the water. ‘good thing i can breathe this stuff,’ Sans thought ruefully as he dragged himself into water deep enough to start swimming. Hopefully sleeping in a saltwater bed every night would stop these involuntary transformations, the loss of control was so embarrassing.

Once out in the open water he started singing. It was faltering and unsure, Sans could barely remember the words that used to flow from his teeth like water. Hopefully it would be enough. If he thought he could remember the way he’d have swam from the estuary Ebott River spilled into, but he wasn’t sure he could remember. Instead he called out to his long lost relatives and hoped they would come.

Sans’s voice, rusty from long disuse, started to give out. He turned back towards shore, sluggishly making his way to the shallower water. He hadn’t heard a single note in response. Perhaps it was too far and they couldn’t hear him, or they couldn’t understand his mangling of what was once his native language. Maybe he could talk to some of the other recently freed monsters who lived in the ocean now, see if they could help him search for ocean natives.

He broke the surface and came in as far as he could before the water was too shallow to swim. He tried forcing a transformation, but his magic refused. Of course, he’d have to crawl out.

“SANS! DID YOU GET A RESPONSE? ARE THEY WITH YOU?” Papyrus came running over and promptly picked Sans up.

“heh, nah. guess they’re too far or something, probably didn’t hear me.”

“THAT’S TOO BAD. WELL, LET’S GET YOU DRIED OFF THEN. UNLESS YOU WANT TO STAY IN THE OCEAN A LITTLE LONGER?”

“i’d rather just go home.”

“ALRIGHT THEN.” Papyrus carried Sans over to where he had been keeping their things, on top of a particularly large and smooth bolder. He laid Sans down and started digging for the towels they had brought. Sans found just being out of the water was enough to force a reluctant transformation, an improvement on having to not just be dry but dry for a while before it finally happened. That’s a good sign. Soon Papyrus had him dried off and dressed again, but rather than gather up their things to leave like Sans expected, he sat down and stared at the ocean.

“uh, papyrus? aren’t we gonna head home now?”

“YOU KNOW, I’VE ONLY SEEN TWO SUNSETS SINCE THAT FIRST ONE, AND THIS ONE IS SO PRETTY. LET’S STAY A LITTLE LONGER.”

“sure, that sounds nice.” They both sat down, Sans leaned back on his arms and watched the sun, already half sunk into the ocean, slowly snuff itself out. Then the stars came out, one by one. Sans counted them, slowly able to start identifying them when enough came out to recognize constellations. The moon rose over their backs, heavy and gibbous. Sans didn’t say anything, this was nice and Papyrus would say when he was ready to go.

Sans was the first to hear it, a high hum from the ocean. Then another. And another… He had been laying on his back to better watch the stars, but sat up straight and stared out at the ocean. Papyrus sat straighter too.

“WHAT IS IT? IS IT THEM?”

“sh!” Sans listened harder, he thought there were words in the humming. Then he saw the first head pop up, way out to sea and easily mistaken for moonlight reflecting on the water. But then it was moving towards the shore, followed by another and another…

Papyrus squealed, “IT’S REALLY THEM! I KNEW THEY WOULD COME!”

“yeah. it’s… they really came.” Sans tried not to choke on the words, he felt so light he thought he might float away. Instead he stood up and started walking toward the water line. The others were standing in the shallows now, carefully walking towards them. Sans held up a hand in greeting and tried to speak what he could remember of Olde Monster. [h-hi. uh… i am sans.]

[SANS! MY CHILD, IS THAT REALLY YOU?]

[yes, i am sans. i uh… i… was child… lost???] He thought those were the right words, he really wished he had asked Toriel to help him brush up along with Papyrus. He decided to try singing the words this time, it just felt right.

[MY LITTLE LOST GUPPY!] The siren ran to Sans, pulling him into a tight hug. The rest must have decided that was all they need, more came to join in a giant group hug that soon had Sans buried in a mass of bones.

Sans laughed, [i missed you very much!]

[WE MISSED YOU TOO, DEAR.]

[WE THOUGHT YOU WERE DEAD!]

[what happened? why were you gone so long?]

[wait,] Sans said in confusion, more questions were thrown his way, more sirens were talking and shouting excitedly. [slow, please. talking hard… very hard.]

{SANS WAS TRAPPED UNDER A MOUNTAIN.} Sans looked up to see Papyrus standing nearby, a wide smile on his face.

[he talks funny,] one of the sirens commented.

[AT LEAST HE’S NOT STRUGGLING LIKE THIS SILLY GUPPY.]

[not a guppy,] Sans grumbled.

[TRAPPED UNDER A MOUNTAIN?] The first siren asked, Sans was pretty sure they were his mother. Or maybe they were like Toriel and called everyone “my child.”

“AH, THE BARRIER, YES?” One siren asked from the outer edges. “WE MET SEVERAL NEW MONSTERS, THEY EXPLAINED IT ALREADY.”

“oh thank god,” Sans said in relief. “it’s been so long i can’t really remember the language.”

“HELLO, I’M PAPYRUS! IT’S VERY NICE TO MEET YOU ALL!”

[WHO IS THIS?] Sans’s mother asked. [THEY SEEM VERY NICE, IS THIS YOUR PARTNER? THEY’RE VERY HANDSOME FOR A LAND MONSTER.]

“oh my god,” Sans groaned.

{WE ARE BROTHERS!} Papyrus said with a grin. {AND I AM VERY HANDSOME ALL THE TIME.}

[OH, BROTHERS. THEN I AM YOUR MOTHER TOO.]

{WOWIE! SHOULD I CALL YOU MOTHER?}

[SO FORMAL, JUST CALL ME ‘MOM’.] She finally let go of Sans, only to pull Papyrus into a hug.

* * *

As former queen and mother of monsterkind’s liberator and unofficial mascot, Toriel found herself thrust into politics far more often than she was happy with. Too often she would go along with Frisk to attend dinners, speeches, and various meetings. As brother of monsterkind’s self proclaimed ambassador Sans found himself in those exact situations right alongside Toriel. At one such event, some sort of dinner/conference combination that had everyone walking around with plates of hors d'oeuvres rather than sitting down to dinner like civilized people, Toriel approached Sans. He expected her to start telling him bad puns and worse knock knock jokes to keep them distracted from how uncomfortable they both were. Instead in her most solemn voice she said, “Papyrus has told me a great deal about the sea monsters and those of us Underground monsters who have returned to the ocean.”

“oh yeah? well, when your brother is ocean-born himself i suppose that makes it kind of a big focus.”

“Indeed. Well, as you know we are attempting to zone and approve land to build monster focused communities on.”

“sure, papyrus was talking about buying some abandoned buildings in the city and other decrepit areas for renovation.”

“Ah yes, to help with integration. But what I was thinking of was a bit different. Specifically we have our eye on an isolated cove and the land around it just a little ways outside the city limits. The theory is it would make a lovely spot for monsters who wish to live next to the ocean as well as a protected place for sea monsters who wish to interact with land monsters and humans.”

“oh, that sounds really cool.”

“And of course we will need someone on hand to act as a sort of intermediary between the two groups.”

“a kind of lesser ambassador, huh?”

Toriel smiled, “Something like that.”

“and i’m first, second, and third for the top of a very short list, right?”

“You are uniquely qualified, my friend.”

Sans laughed, “guess i am. sure, i’ll do it. i already do all that kind of stuff anyway while helping papyrus out.”

“Thank you, my friend. And of course there will be areas set aside to build homes, you two will get first pick.”

“neat, i hope we can pick something right on the water, papyrus has his heart set on a basement moon pool.”

Toriel laughed heartily, “I am not sure what that is, but I am quite sure all things are possible.”

* * *

The cove had been approved and a small seaside town was being built along its outer edges. Many monsters had chosen to have homes built there, the lure of fresh ocean air, a small monster centered community, and being an easy distance from the city were all cited as wonderful reasons to move there. There was even talk of a few underwater buildings in the lea of the rocks protecting the cove in the planning stages. Of course, due to the expected popularity of the spot among sirens, leviathans, and other sea monsters, ships with human crew or passengers were warned away. A network of buoys and several repeating radio broadcasts in several languages were hoped to be enough to warn away any who got too close. Papyrus had hopes the system would prove to work well and would allow sea monsters to build their own seaside communities all around the world. “A SAFE HAVEN FOR SEA MONSTERS,” he had called it.

Asgore was so enamored with the phrase he had suggested it as a name for the growing town, everyone was too polite to tell him what a bland name it was. If the F in ‘Safe’ happened to somehow get dropped out while filling out the paperwork and the town became known as ‘Sea Haven’ instead, well, that’s just bureaucracy for you.

Sans had been excited when he told his family about it, and they had been just as excited to be told. Today he was taking them to visit, a place they can sing and play in the shallows and not worry about being attacked by frightened humans.

[see the rocks like arms?] Sans pointed to the entrance to the cove, granted it was a little hard to see underwater but he was still used to thinking of landmarks from above. [with the… the sand uh… spilling out.] Okay, so he still had some trouble with the language, cut him some slack!

[THAT’S SEA HAVEN?]

[yup!] They were close enough now that Sans decided to surface. [about here is where the uh… the safe starts.]

[HUMANS REALLY CAN’T COME HERE?]

[no, they can. there are warnings for the ships, and some can’t go in the cove, but they can still sail out here if they want.] Sans tried not to frown, the cove technically wasn’t privately owned since the Monster Social Bureau that was organizing all this wasn’t technically capable of privately owning anything. But they did at least get the inside of the cove zoned so no commercial craft could go in. They were also lobbying to be able to put heavy restrictions on the kind of emissions and sound pollution allowed inside the cove, something that was very likely to happen between the number of homes in Sea Haven and the planned underwater buildings.

[IF HUMANS KNOW WE’RE HERE, THEY WON’T WANT TO COME.]

[YOU SAY THAT, BUT I’VE HAD HUMANS CHASE ME BEFORE.]

[there are monsters who live here who uh… their role is to protect monsters. that means us too.] Like Undyne, who he couldn’t wait to introduce to everyone. He was sure they’d love her.

They passed into the cove at that point, Sans slowed so he could point to the inside of the ‘arms’ and tell them a little about the buildings that were being planned. Although no one had officially stated it, Sans was pretty sure they were waiting to consult siren architects before starting. And even if not, he at least hoped they would talk anyway. He personally thought the spires and arches of water smoothed stone softly lit blue by magical plant-life of the one siren city he’d been to was pretty. It reminded him of Waterfall, or maybe Waterfall had reminded him of it since that was the city he was born and raised in. Well, as raised as he had been before falling into the Underground.

Then he took them ashore where a small group of people were waiting on the beach. The looks on everyone’s faces as the shimmer of sirens came calmly walking up the shore was priceless. He even made sure his (second??) cousin, the one who spoke the most English, was up front.

“Holy cow, Sans!” Undyne yelled as she walked towards Verdana. “You didn’t warn me about this!”

“about what?” Sans asked from the middle of the group.

“That you all look the same! Do you all sound the same too?”

“THAT’S A VERY RUDE THING TO SAY.” Verdana crossed his arms and glared at Undyne.

“Wait… you’re not Sans, are you?”

Sans raised his hand, “over here.”

Undyne pointed at him and snarled, “YOU DID THAT ON PURPOSE!”

“yup.”

Asgore walked up and put a hand on Undyne’s shoulder. {Hello, it is very nice to meet you all. I am Asgore, former king of the Underground.}

There was a murmur of various [Hello]s from the shimmer.

{Would you like a tour? I am sure Sans already showed you the cove, but the town is in land a little. It is still small, but very nice so far.} Asgore motioned up the wide path leading from the beach to the first few buildings beyond the sand. As Asgore spoke, Undyne started making faces at Verdana behind Asgore’s back. Verdana started making faces as well. Undyne responded by flexing her muscles, something she knew a skeleton couldn’t really do. Verdana decided to show off by picking up a couple sirens and balancing them on his flexed arms. Yup, those two were going to get along fantastically.

* * *

“AND THIS IS SANS’S ROOM.” Papyrus opened the door and flourished his arm about the space. Their friends all poked their heads through the doorway curiously.

The floor and walls were tiled, there was even a drain off to the side. Right next to Sans’s ‘water bed.’ There was also a towel rack, a night stand, a dresser, and a bookshelf (up on stilts), and amusingly a fishbowl with what appeared to be a plastic fish floating in it.

Undyne walked into the room and nudged Sans’s bed with her boot, “What’s this?”

“my bed, what else?”

“It’s a kiddie pool.”

“eh, it works.”

Alphys walked over and started inspecting it. “And wh-what’s this?”

“it’s a pump, for water circulation.”

“IT’S SUPPOSED TO ONLY BE A TEMPORARY SET UP UNTIL WE CAN GET SOMETHING BETTER, WHICH SHOULD BE NOW. WE HAVE A PERMANENT HOME, SANS.” Papyrus glared meaningfully at Sans.

“like i said, this works.”

Papyrus rolled his eyes while Alphys and Undyne gave each other A Look (TM).

“It seems you have been a-salt-ed.” Toriel was holding up a container of salt that had been sitting on the nightstand. Frisk was standing next to her, leaning close to the pool. They pulled back a hand when they realized everyone’s attention was pointed in their general direction.

“yeah, it’s for the water.”

Undyne made a noise of disgust, the A Look (TM) between her and Alphys somehow intensified.

“WELL AT LEAST YOU GET TO SEE HIS ROOM BEFORE THE SOCK AND TRASH EXPLOSION. NOW MY ROOM, ON THE OTHER HAND, IS VERY COOL AND WORTH LOOKING AT!” Papyrus proudly led the way next door, where he had his action figures already set up in a tactical display. Alphys lingered at the back of the group, hardly paying attention as she tapped furiously away at her phone. It would be two and a half weeks later that Sans found out what that meant for him.

“COME ON, SANS! WE HAVE A SURPRISE FOR YOU! IN YOUR ROOM!!!”

“that’s cool, bro. but who’s ‘we’?” Sans grinned placidly as he let himself be led up the stairs.

“GO IN YOUR ROOM AND FIND OUT, NYEH HEH HEH!”

“i dunno bro, think i’ll just stay on the couch and let the surprise build.” They were at the top of the stairs now and Sans was slowly ambling towards his door. He reached for the handle…

“NO WAIT! CLOSE YOUR EYE SOCKETS. COVER THEM! NO PEEKING!!!”

Sans obligingly closed his eye sockets and put his hands over them. He heard Papyrus open the door and push him into the room.

“OKAY!”

Sans opened his eyes.

“Tada!” Undyne and Alphys were standing in the middle of his room, both on either side of where his ‘bed’ used to be. In its place was a large glass tank with rounded corners he could see was filled part way with water, a comfy looking layer of sand on the bottom, and bubbles rising in the corner. Next to the tank was a set of stairs, squinting he could see they were mirrored inside the tank.

“Wh-what do you think?” Alphys asked timidly.

“whoa… you made this for me?” It was the perfect size, wide as his old bed had been and more than long enough for his tail while also deep enough to sleep comfortably in.

“We sure did, punk!” Undyne grinned and moved to sling an arm over Alphys’s shoulders. “Alphys did the design and all of the technical work while I provided the muscle.”

“She sure did,” Alphys said dreamily, then shook her head. “A-and gave advice! Undyne knows w-way more about water tanks than I do. Plus got me in c-contact with one of your relatives.”

“AND I, OF COURSE, HELPED MOVE EVERYTHING INTO THE HOUSE WHILE KEEPING YOU EXPERTLY DISTRACTED.” Papyrus looked so proud of himself.

“thanks guys, this is really cool.”

“T-try it out!”

“Yeah! We wanna make sure it’s comfy!”

Sans shrugged before just stripping his clothes off, leaving them wherever they landed. He decided to use the provided stairs, right next to the towel rack, and easily slipped into the water. He settled on the bottom, face up with his hands laced behind his head. Yeah, the sand was pretty comfortable, the water was just the right temperature and salinity, and the sound of any motors was pretty muffled. All he heard was a gentle hum, but even that was hard to pinpoint over the sound of the bubbler. He shifted around, even turning to face the other way. It was a bit tight of a turn, but nothing terrible. So long as he didn’t spend the whole night circling his new water bed he’d be just fine.

Sans surfaced and slung his dripping arms over the edge of the tank, “it’s perfect. thanks you guys.”

Alphys jumped up and down in excitement. “That’s great! We made sure your uh… your ‘bed’ has everything you need: skimmer, filter, air pump, TWO powerheads to make sure there’s enough circulation, and a top of the line water testing system. That way if you want to add some plants or something to make it more comfortable, or even one of these little guys,” Alphys held up her phone to show a picture of an algae eating fish, “to keep the tank clean you don’t have to add anything or anything.”

“WHICH I FULLY SUPPORT!”

“Oh! And I forgot to show you something else.” Alphys motioned for Sans to get out of the water. He shrugged and did so, climbing back up and down the stairs. He wondered how quickly that would get old. Papyrus handed him a towel, Sans accepted it and draped it over his shoulders. “Th-there’s a lid for the tank, to keep anything from falling in during the day.”

“I THINK HE FORGOT THAT’S WHAT THE TARP WAS ORIGINALLY FOR.”

“S-so all you have to do is push this button,” Alphys pushed a button attached to the wall. There was a mechanical sound followed by movement as a lid lifted from between the wall and the tank, then rotated into place over the tank. “You just need to push it again and it uh… it’ll just go back out of sight. A-and don’t worry! It’s designed so even if you’re inside when it’s activated it’ll be easy to lift off you. Actually, now that I think about it maybe I should make a second button that’s inside the tank too. I’ll have to make sure it’s not just waterproof, but also rustproof because of the saltwater…”

“And she’s off. Isn’t she so passionate and nerdy?” Undyne chortled as she looked at Alphys affectionately.

Sans hooked his fingers under the lid and gave an experimental pull, it easily lifted. “wow, you really thought of everything. thanks again, guys, you really outdid yourselves.”

“WHILE THIS IS BOTH VERY KIND AND VERY WELL MADE, I DON’T THINK YOU CAN POSSIBLY SAY THIS OUTDID THE PURE ENGINEERING GENIUS THAT IS METTATON.”

“yeah, sure thing papyrus.” Sans and Undyne both laughed.


End file.
